Ever since the formation of the global network of interconnected computing devices such as the Internet, there is being a huge emerging of various communication formats enabling these computing devices to communicate among themselves. This has created various services for users in business and non-business areas. In later half of 1990's we saw the boom of the Internet. A whole set of new services and content became available to the consumers during a short, revolutionary and hype intense period. That period introduced e-commerce, Internet Service Providers (ISPs), Portals, eyeballs game, dotcom companies and even the new economy.
However, many of the communication formats were originally designed for traditional packet based transmission, where association to real time event typically lacked. An example of such a communication is the web pages and web surfing. Also many trusted application such as banking could be taken care with possible delays. Even the fastest data communication ways such as Asynchronous Transfer Mode (ATM) were designed, despite of the ultimate data transfer speed, to quite delay tolerant environments. Lately the telecommunication industry has been highly focused on their leap towards using IP for telecommunication services. As one alternative, Multiprotocol Label Switching (MPLS) can be chosen as the bearer of IP, especially in large backbone networks.
However, the MPLS carries the heritage of delay tolerant based data communication such as the ATM, despite offering a fast way to transfer data. Consequently, there are still some remains of the ATM in the MPLS. One example is the principal design for applications substantially based on non real time or alternatively expressed as delay tolerance.
Examples of such approaches have been presented according to standardization specification drafts of the ITU-T: Y.1710 “Requirements for OAM functionality in MPLS networks” COM 13-14-E July 2002, Y.1711 “OAM mechanism for MPLS networks” COM 13-15-E July 2002, and Y.1720 “Protection Switching for MPLS networks” COM 13-R 14-E June 2001, all three incorporated herein as a reference, where Connectivity Verification (CV) packets are sent 1/s (1 per second). This standard solution provides a fault detection time of three seconds from the fault event.
Existing MPLS Path failure-detecting mechanism can inform both ends of the backbone about failures using the backward and forward detect indicators (BDI and FDI), although typically Label Switched Path (LSP) has a one-way character. The Connectivity Verification (CV) packets check the network for Path-specific errors like mis-merging or swapped Paths. A Path failure has occurred when defects on three consecutive CV packets have been detected. This means that it takes three seconds before a failure alert for a Path error can be detected and sent further.
A disadvantage of the above-identified standards is that the solutions according to the above-identified standards are not adequate for any communication or connections requiring real time functionality. Moreover, the switch-over time is not fast enough with substantially real-time based connections, where a switch-over is typically required in less than 50 ms.
In view of various inherent limitations of communication and systems between computing devices, it would be desirable to avoid or mitigate these and other problems associated with prior art. Thus, there is a need to have a fault detection and switch-over functionality for real time application.